Web-drying device



Janu l7, 1930. A. E. F. MooNE 1,742,355

WEB DRYINCY DEVICE Filed Feb. 1.5. 1926 OOOQOOOOO opoooeco INVENTOR ALBERT E. F. MooNE ATTORNEY BYMWM am. v, :93o

maar n. l. xoom;

or carence, rumors wan-name mon f Application llled February My invention relates to an improved mechanism for drying webs felt in the course of their manufacture, :y which the webis effectively and rapidly dri s or nearly dried, by suction devices arranged toremove the moisture from the web as it j passes through the machine by the actionofa diierence 1n atmospheric pressure on the two sides of the web, or more s pecically by theaction of atmospheric pressure on one side of the web and sub-atmospheric pressure on.

the other'thereof. Y As is well known in connection with the manufacture of paper and sheet felt, the web in either case, after it is collected and formed in any suitable manner bydevices well known in the art, carries a great deal ofmolsture which must be removed in order that the web may ass through the remalning steps of manu acture to result in the finished product.

The means most commonl used to accomlish this result, consists o revolving heated rums over which the web passes to dry 1t.

This mode of drying is open to eitherone of. as two objections; first, slow motion must be 1mparted to the web if but few heating drums are employed, or second, a large number of must be used if a rapid motlon is imparted to the web, on account of the temperal d tures necessarily bein limited if the web is to be uninjured, an the relativel small amount of drying possible with eac drum unless the motion of the web is so slow in passing over it as to be prohibitive from the standpoint of commercial manufacture. am'aware that it has been proposed heretofore to employ vacuum devices of one kind or another to in Part remove the moisture from the 'web. As ar asI- am aware, however, these devices are open to the objection that the subatmospheric pressure employed has not been effectively applied to the web forthe maxi-Y mum possible time interval represented "bythe passa e of the web through the vacuum devices. ore s ecilically, the devicesl heretofore proposed, ave employed a perforated Y Y g' drum or drums over which the web in i wet condition is` passed and a zone of. subrelatively hmlted extent as toits application of paper pulpl and atmospheric'pressure has beenv produced, of-- to the web and further, thedevices employed have resulted in marked fluctuation of the sub-atmospheric effecten the web, due to the nature of the devices employedforreducing the latmospheric pressure throu hout the vacuum zone, as` a result 4of whic with -a vdegree of sub-atmos heric pressure that willY not injure the web hut small drying results, and -where the sub-atmospheric high enough for dryin the web, t e pressure 1s not uniformly 4app 'ed to the web and danger of tearing results. Thus in either case the action is noteicient. In carryingout my invention I employ a. perforated drum or drums and means for '35 ceding' the wet web over' the surface of said vor drums, and' provideia sub-atmospheric pressure-chamber directly in contact with. the inne'r surface of thev'drum in each4 case, so thatthe desired condition of subatmospheric pressure is uniformly maintained in the chamber and uniformly applied to the web being dried throughout'its entire passagethrough the vacuum zone. Furthermore, by 'my construction the wet web is caused to 75 engage the perforated drum in each case, be ore its entry vvinto the vacuum zone i it is introduced into the vacuum 'zone without an'gerous air pressure being exertedupon it, and 4after passing lcompletely through the vacuum zone, during which it is continuously subjected to the maximum sub-atmospheric- E'essure permitted bythe nature of the web ing dried Without injurin it, the web passes v from thevacuum zone sti in vcontact with `the perforated drum, so that it ifs readily removed-therefromin leavinl the machine or passingtothenextperforate drum, and without dangerof tearing the web. important v feature of my resent invention-is arranging 90 twoperforate drums of the kind referred to so'tha't the web first passes over one of said drums and lthrough its vacuum zone and v, thereafter. eavesthe first perforated drum -and passesaround the lsurface of the Second 95 perforated drum -and through its vacuum zone, in such a manner that one surface'of the web engages the first .drum and the other surface ofthe web. engages the-second drum. In

fthismanner I remove the'moisture from both 10o ressure is surfaces of the web by sub-atmospheric pre'ssure and I iind that this produces a highly efiicient extraction of moisture from the web, for I have found that where it is attempted to remove the moisture from the web by subatmospheric pressure exerted on but one side of it, the other side of the web isleft relatively Wet, this being particularly true where the web is relatively dense, as is-the case With webs formed from certaln kinds of paper stock, although the same thin@ is true to a less degree with more porous wel-bs, for example webs of felt stock. B my invention I also provide means for rea ily ad'usting the position of the vacuum zone re atively to each perforated drum so that the vacuum zone may be given the most eii'ective relation to the arc of contact of the web on the drum; I further provide devices for readily adjusting the vacuum chamber to compensate for wear and to insure effective relation between the vacuum chamber and the inner surface of application Serial No. 16,100 filed March 17,

1925, now Patent No. 1,577,839, granted Mar. 23, 1926, as'to the subject mattershown in in Figs. 1 to 4inclusive of the drawings, the subject matter shown in Figs. 5 and 6 comprising a modified construction thereof.-

My invention will best be understood by reference to the accompanying drawings showing preferred embodiments thereof .in which Fig. 1 shows one form of my drying machine in end elevation with the end frame nearer the observer'removed for the sake of clearance,

Fig. 2 shows in longitudinal, vertical, sec-V tional view and to an enlarged scale, a part of one of the perforated drums shownhin Fig. 1 and a corresponding art of the vacuum chamber and associated evices for removing the moisture,

Fig. 3 shows in end view one of the shields adapted for use in connection with the perforated drums,

Fig. 4 is a detail view to an enlarged scale of the supporting devices shown in Fig. 2, taken along the lin'e 4.-4 in said ligure,

Fig. 5 is a transverse sectional view to an enlarged scale of part of one of the drying drums and its vacuum chamber, and shows packing devices vvthat may be employed in connection with the vacuum chambers, and

Fig. 6 is a sectional view of the parts shown in Fig. 5, taken along the line 6 6.

Similar numeralsrefer ,to similar parts throughout the several views.

As shown in Fig. 1, my machine consists of two tubular drums 10and 11 mounted for rotation on supporting and retaining rollers '12, 12- for the drum 10 and 13, 13 for the drum 11,. said rollers engaging the outer sur- `faces of the drums so that they may turn cylindrical Iouter edge the end frame nearer the observer beingref moved to more clearly show the construction ofthe machine. i .i

' The drums 10 and 11 have located inside of them and extendin lo 'tudinall thereof vacuum chambers 1 anndgl provided with y surfaces to closely t with sliding engagement the inner surfaces .of the drums 10 and 11,the latter being preferably provided with true and smooth cylin' I drical inner surfaces to permit the it referred to. The :hambers 17 and 18 are provided with outlet pipes 19 and 20 respectively, for withdrawing moisture and air from said chambers. As indicated in Fig. 2 for the drum 10, each of the drums is perforated throughout its entire length, excepting adj acent its end supporting and dri portion, said perforations being indicatedpm Fig. 2 at 10, to form the'only'inlet for air and moisture to the corresponding vacuum chamber. The perforations are preferabl small diameter holes extending entirely trough the drum radially and placed as close to' gether as practical conditions of manufacture will permit. The end and side walls of each vacuum chamber are imperforate, as a result of which any condition of sub-atmospheric pressure which may be produced in' either chamber, is communicated through` the drum perforations in line with the chamber to the web that may be on the outer surface ofthe drum and thus the atmospheric pressure on the outer surface of the web is effective in forcing moisture from the web' through the perforations intoV the vacuum chamber, the side walls of which are inclined:

22 from brackets 23 and 24 respectively, said brackets being in turn mounted on trunniou supports 25 and 26, engaged and rigidly supported by clamping caps27- and 28 respectively, carried by the frame members 16, Said caps being provided with set screws 27 for thispurpose.

The drums 10 and 11 carry near one end thereof external gear rings indicated diagrammatically in Fi 1 at 29 and30, which interme'sh as indica ed, the gearing 30 also vmeshing with a piniony 31 similarly indicated in Fig. 1, said pinion being rigidly secured to a shaft 32 carried in suitable bearings therefor on the end frames 16, to drive the machine.

' The frame members 16 also support between them by suitable bearings, aguiderollias the drum 10, being then led around the bottom and upwardly on the outer surface of the drum 10 until it is adjacent the roller 33 around which it passes t0 be deliveredfrom the machine as indicated. The direction of 'rotation of the drums andthe direction of motion of the web is indicated by the arrows.

The web may be any web of fibrous material made by collecting the fibers from solution in any manner known to the art, whether the resulting web is of paper pulp, felt ber or otherwise, the web being in wet condition when it is delivered to the machine under consideration. As the web passes around the ldrum 11 the sub-atmospheric pressure in the chamber 18 is effective in causing the flow of moisture from the web under the action ofatmospheric pressure on the outside of the web, through the perforations in the drum and into the chamber 18 from which the air and moisture are continuously removed from the outlet pipe 20 by suitable pumping means. This operation is effective 1n removing practically all of the moisture from that surface of the web in contact with the drum 11. The outer surface of *the web however, still contains considerable moisture and this surface 'of the web, which is outermost in ,lits passage around the drum 11, becomes the inner most surface of the web in its passage around the drum 10, where the now inner surface ofthe web-is subjected to the same action above referred to bythe atmospheric pressure in the chamber 17.l In this manner practically all of the moisture is removed from the web and the nearly dry web may be subsequently completely dried by heated drums in the usual manner, the advantage being that the number of heated drums/required to thoroughly dry thev web after theextraction of moisture from it just described, is small, eyen for high velocity of the web, whereas without the extraction of moisture in the' manner described, a Vvery large number of such heated drums is required to completely`remove the moisture from the web, accom anied by a correspondingly large expense or fuel to generate the steam required to heat the many d rylng drums.

In carrying out my invention the drums 10 and 11 aremade of a sui'licient length to accommodate the widest web to be dried by the machine. To accommodate webs of' lesswidth I employ cover strips 35 and 36 encircling thedrums around the portions thereof in angular alignment with the vacuum chaml bers, these cover stri s being preferably placed at the ends of t e drums and having theirv ends secured by suitable retaining devices, for example pins 37 and 38,A to the frame members 16 in such a manner that the lcover strips, which are preferably of thin sheet metal, will prevent ractically all air How through the perforations under them into the vacuum chambers and yet at the same time permit the drums to rotate freely un der them. The coverstrips are\taken of a width to cover that part of the outer surfaces of the drums that is not covered by the web` being dried. The cover strips are of similar construction, onefof them for example a cover strip y35 being shown in end elevation in Fig. 3.

The vacuum chambers substantially the same construction as each other and they are similarly supported on the frame members of the machine s o that detail reference to the manner of supporting but one of them will suffice. As indlcated in is extended outside of the machine to connect with any desired form of pumping mechanism, indicated diagrammatically at 40 from which a discharge pipe 41' extends. It is immaterial what form of pumpin mechanism is employed, the only requisite eing that it shall have suiiicient capacity to produce the desired condition of sub-atmospheric pressure in the chamber 17 and remove from the chamber 17 all of the moisture that may collect in it adjacent the end of the pipe 19.

As'indicated in Fig. 2, the end wall of the chamber 17 ,has secured thereto in any suitable manner, a reinforcing plate 42 through which the. pipev 19 extends, said plate carrying at its. lower edge an outwardly projecting -iange43zf lAs indicated in Figs.` 2 and 4,

the trunnion 25 Vis securely heldin place by a cap 27 through'which set screws may extend if desired as indicated at 27 to further restrain the trunnion from rotary movement in its support. Theinner end of the trunnionl 25 has `rigidly secured thereto a bracket 23 carrying on its upper end a U-shaped iange member 44 forming :a supporting surface for the wedges 21 disposed' between the fiange member 44 and the flange 43 secured to the vacuum chamber. The flan e member 44 carbons 46 extend through the ila-nge 43, the.

wedges 21 and the flange member 44, to clamp the partsgtogetherin any desired adjustment. It will be understood that theconstruction los l v` 17 and 18 are of orting devices described for the chamin connection with Figs. 2 and 4, is

, of su ber duplicated at the other end of chamber 17.

As a result of the construction described, it

5 will be observed that the chamber 17 may be given any desired angular adjustment by releasing the caps 27 andl setv 'screws carried thereby, without modifying thel fit of the chamber against the inner surface of the drum, since the trunnions 25 are co-axial with the drum. In this manner the chamber 17 may be given such an angular relation to the desirable that the vleadin 20 with the drum by the suction eiects produced through the perforations; it is also desirable that the traihng edge of the vacuum chamber shall be suiiiciently back of the line of departure of the web from the surface of the drum, to insure that the web is in engagement with the outer surface of the drum for at least a small angle after passing from the zone of sub-atmospheric pressure, so that there will be no tendency to tear the web by attemptin to remove it from the surface of the drum w ile it is subject to the action of the sub-atmospheric pressure.

It will also be understood from the description just made in connection with Figs. 2 and 35 4 that each end of the vacuum chamber may,

be adjusted radially ofthe drum independently of theother end, and without changing the angular position of the chamber, either to secure the sliding engagement described between the vacuumw chamber and the inner surface of the drum, or to move the vacuum chamber slightly to compensate for wear that may occur after continued use of the machine.

In making the perforations in the drum,

it is desirable that said perforations shall be of suiliciently small diameter so thata required degree of sub-atmospheric pressure may be produced in the vacuum chamber to effectively remove the moisture from the web, without however, appreciably disturbing the material of the web by the suction action upon it. Where the web 1s composed of material having long fibers, the perforations may be relatively large, particularly if the web is of substantial thickness; on the other hand, where the web is thin and consists of relatively short fibers, for example where the web is of paper stock, it is desirable that the perforations 10EL be of very small diameter. For any diameter of the perforations 10, required for the drying of webs of any particular kind, it is desirable that as many perforations shall be made through the drum as permitted by mechanical considerations, to the end that as much as possible of the surface of the web passing over the vacuum chamber, shall be subject to the suction action.

In Figs. 5 and 6, I illustrate a form of packing device that may be used to advantage with the vacuum chambers. In this construction, the vacuum chamber 1'2"l is provided with packino strips 50, 50 in suitable grooves provided therefor in the outer ed s of the inclined sides of the chamber, an is also provided with similar arcuate packing,

strips in the outer edges of its ends, as shown for one of said ends at 51. Each of the packing strips 50 is a sliding lit in its supporting groove and is held outwardly against the inner surface of the drum 10, by springs 52 mounted in bores therefor in bosses 53 rojectmg from the side wall of the chamlber, each of said bosses carryin also an adjusting screw 54 engaging one en of a spring 52, to place desired stress on said spring, by which the strip 50 is caused to bear with desired pressure against the inner surface of the drum 10. Each end strip 51.is similarly supported by springs 55 and screws 56 supported in bosses 57, as indicated for one end of the chamber 17 in Fi 5, it being understood that the end of `sa1d chamber which is not shown in Fig. 5, is provided with a similar strip 51, similarly supported. It will be understood that as many springs and adjusting screws may be used'with each of said packing strips, as necessary to exert desired pressure on said strip. Thesescrews also provide a ready means for compensating for wear on said strips, and by adjustin these screws from time to time, any desire bearing pressure may be maintained on said strips, even for a considerable amount of wear of said strips. In some case this construction may be employed as the sole means of radial adjustment of the outer edges of the chamber 17, and the wedges 21 may be omitted; in other cases, it may be advisable to employ the adjusting wedges 21 in addition to the packing strip adjustment. The packing strips may be made of an suitable material, for example, metal, woo or packing composition of any nature that is adapted to the purpose described. Theends of the strips 50 and 51 closely it each other to prevent undue leakage into the chamber at these points.

The vacuum chamber construction shown in Figs. 5 and 6, may be employed with either or both of the drums shown in Fig. 1, and the machine in other respects may be constructed and operated as above described.

While I have shown m invention in the particular embodiment a ove described, lit will be understood that I do not limit myself to this exact .construction as I may employ equivalents known to the art at the time of the filing of this application and my prior application referred to, without departing from the scope of the appended claims.

What I claim is:

1. In a web drying machine, the combination of a rotary tubular drum having perforations through its cylindrical wa1la vacuum chamber havin an open side against .the inner surface o? the drum, a delivery pipe extending from said chamber, trunnions separate from said delivery pipe supporting said chamber againstrotation, and wedges for adjusting saidchamber radially of the drum.

2. In a web drying machine, the combination of a rotary tubular drum having perforations through its cylindrical wall, a vacuum chamber having an open side againstthe inner surface of the drum, a delivery pipe extending from said chamber, trunnions` separate from said delivery pipe supporting said chamber against rotation, holding .devices for said trunnions permitting angular ad'ustment of said chamber, and wedges for a justing said chamber radiallyof the drum.

3. In a web drying machine, the combination of a rotary tubular druml having perforations through its cylindrical wall, a vacuum chamber having an open side against the inner surface of the drum, a delivery pipe extending .from said chamber, trunnions separate from said delivery pipe supporting said chamber against rotation, and wedges for adjusting said chamber radially of the drum, said chamber having packing'devices around the edges of its open side comprisin strips of packing material carried by sai edges and springs between said strips and said chamber holding said strips against the inner surface of said drum.

4. In a web drying machine, the combination of a rotary tubular drum having perforations through its cylindrical Wall,` a vacuum chamber havin an open side against the inner surface of the drum, a delivery pipe extending from said chamber, trunnions separate from said delivery pipe supporting said chamber against rotation, and wedges for adjusting said chamber radially of the drum, said chamber having packing devices around the edges of its open side comprisin strips of packing material carried by sai edges and springs between said strips and said chamber holding said strips against the inner surface of said drum, andtensioning screws engaging said springs to adjust the pressure thereof.

5. In a web drying machine, the combinai tion of a rota tubular drum having perforations through its cylindrical wall, a vac uum chamber havin an open side against the inner surface of te drum, a delivery pipe extendin 'from said chamber, trunnions separate m said delivery pipe su porting sald chamber against rotation, an wed for adjustin said chamber radially of t e drum, said c amber havin grooves in its edges around said open sie, and packing strips in said grooves to engage the inner suri face of saiddrum.

6. In a web drying machine, the combmation of a rotary tubular drumhaving perforations through its cylindrical Wall, a vacuum chamber having an open side against lthe inner surface of the drum, a delivery pipe extending from said chamber, trunnions seption of a rotary tubular drum having perfo-l rations through its cylindricalv wall, a vacuum` chamber having an open side against` the inner surface of the drum, a delivery pipe extending from said chamber, trunnions separate from said delivery pipe supporting said chamber against rotation, and wedges for adjusting said chamber radially ofthe drum, said chamber having grooves in its edges around said open side, packing strips in said grooves to engage the inner surface of said drum, springs between said strips and said chamber to -hold said strips against said drum with desired ressure, and adjusting screws engagingsai springs 'for changing the pressure thereof.

In witness whereof, I hereunto subscribe my name thisl 8th day of February, A. D.

ALBERT E. F. MooNE. 

